1. Field of Invention
Aspects of the present invention relate to methods and systems for monitoring an area in space via an image capturing device. More particularly, aspects of the present invention relate to monitoring an audience in an area in space.
2. Description of Related Art
A number of important applications require the detection and counting of people to ensure, for example, security, safety, and to support site management. Examples include the monitoring of audiences located before a liquid crystal display (LCD) or other type of screen, the estimation of queue length in retail stores, and the flow density monitoring of entry points, bus terminals, train stations, and the like. Although person detection and counting systems are commercially available today, there is a need to address the challenges of real time ever moving audiences.
A variety of human detection technologies are well known in the related art. Audience counting systems via video provide a count of people entering and/or exiting a particular location, passageway or establishment. For instance, an audience counting system may provide a beam, e.g., an infrared beam, across the passageway to be monitored. As people enter or exit the passageway, the beam is temporarily interrupted, and a counter increases by one increment each time the beam is interrupted, thus counting the number of people that have crossed the beam. The audience counting system detects this interruption and increments or decrements its net internal count of people entering the passageway.
In addition, other human counting systems that report on the direction of travel of people through a particular passageway are available in the related art, but these systems tend to be complex and expensive. For example, directional counting systems utilize a foot-activated pressure-sensitive platform at the entry point of the passageway. Based on a pressure profile related to the engagement of an individual's foot with the platform, the system predicts the direction of travel of the individual. However, as discussed above, these systems are complex and expensive.
Other related art human counting systems are coupled with electronic article surveillance systems and an alarm management unit. In such systems, for example in large department stores that have a large number of articles that can be electronically tagged and a large number of people, the alarm management unit receives the electronic article surveillance data signal from the electronic article surveillance system and a human count signal from the human counting system, for facilitating correlation of electronic article surveillance and human count data.
However, none of these related art tracking-based techniques provides accurate results in precisely determining a number of people present within an area at least because human tracking under occlusion is a problem that has not yet been solved, and these systems tend to be inefficient because most of the computational power consumed is used to track the individuals, leaving little processing power for other tasks such as activity monitoring and behavior analysis. Additionally, some of these techniques are limited by the camera position, such as the overhead mounting requirement, and some require multiple cameras to build a three-dimensional image. Accordingly, these requirements are fulfilled at the expense of computing power.